HONOLULU — A former B-2 stealth bomber engineer from Maui who is accused of selling military secrets to China is due to face trial in federal court this week.

Noshir Gowadia has pleaded not guilty to 21 counts, including conspiracy, violating the arms export control act and money laundering. The indictment accuses Gowadia of helping China design a cruise missile with stealth capabilities.

The trial comes some 4 1/2 years after Gowadia's arrest and more than three years after his trial was originally scheduled to be held. The 66-year-old Haiku resident has been in federal detention since his October 2005 arrest because a judge ruled he was a flight risk.

Jury selection is scheduled to begin Tuesday at U.S. District Court in Honolulu, and opening statements are expected the following day. The trial is expected to last at least two months.

Ashton Gowadia said his father is looking forward to defending himself.

"Dad is very confident that he will be found 100 percent innocent of any crimes. He is looking forward to finally getting his day in court," the younger Gowadia said in an e-mail to The Associated Press.

Larry M. Wortzel, commissioner of the U.S.-China Economic and Security Review Commission, said the trial will be closely watched by the intelligence community, the FBI, and military because it's one of a series of major cases involving Chinese spying on the U.S.

Chinese-born engineer Dongfan "Greg" Chung was sentenced last month to more than 15 years in prison after he was convicted of six counts of economic espionage and other federal charges. A judge found him guilty of storing 300,000 pages of sensitive papers, including space shuttle details, in his Southern California home.

Investigators learned about Chung while probing Chi Mak, another suspected Chinese spy living and working in Southern California. Mak was convicted in 2007 of conspiracy to export U.S. defense technology to China and sentenced to 24 years in prison.

Wortzel said key information flowed to China because of Gowadia.

"The loss of such information can reveal potential vulnerabilities in American defense systems and can help a hostile military to target those weaknesses in case of conflict," Wortzel said in an e-mail. "These losses can put U.S. service members at risk."

Prosecutors allege Gowadia helped design an exhaust nozzle for China that gives off less heat, making it difficult for infrared detectors to find the missile. They say Gowadia pocketed $110,000 over two years for his exhaust nozzle design.

The indictment alleges he made six trips to China from 2003 to 2005, conspiring to conceal some of his visits by getting border agents to leave immigration stamps off his passport.

He's also accused of attempting to sell classified stealth technology to the Swiss government and to businesses in Israel and Germany.

The trial was initially due to begin in early 2006, but motions to suppress statements, the need for lawyers to obtain classified clearances, and other issues repeatedly pushed back the date. Gowadia had to switch to a court-appointed attorney after one year when he ran out of money to pay the Washington, D.C.-law firm he initially hired.

Gowadia's defense team suffered several setbacks during the pretrial period.

A judge last year denied a motion by Gowadia's lawyer to suppress statements Gowadia made to government investigators during 13 days of questioning before his arrest.

Two other judges later denied a defense motion that Gowadia was incompetent to stand trial on the grounds he suffers from a narcissistic personality disorder.

Gowadia moved to the U.S. from India in the 1960s for postgraduate work. In 1968 he joined defense contractor Northrop Corp., now Northrop Grumman Corp., where he designed elements of the B-2.

He became a U.S. citizen in the 1970s and retired from Northrop in 1986, two years before the B-2 made its public debut.